Absorption of daunorubicin and etoposide drugs by hydroxylated and carboxylated carbon nanotube for drug delivery: theoretical and experimental studies.

Anti-cancer daunorubicin and etoposide drugs are mostly used in chemotherapy medicine to treat a wide variety of cancers. Many of the side effects and specific delivery to a target tissue are the main challenges of using chemotherapeutic agents. To avoid serious toxic side effects and improve treatment outcomes, functionalized carbon nanotubes (f-CNTs) are considered promising nano-carriers for the delivery of chemotherapeutic drugs to cancerous cells. We examined the effects of -OH and -COO- groups on CNTs surface for absorption of two anticancer drugs including daunorubicin and etoposide using molecular dynamics simulation and experimental assays. To evaluate the absorption of each drug in each CNT, the complexes of drugs/CNTs in water were simulated separately. Theoretical investigation demonstrated that CNT-OH and CNT-COO- are more suitable for absorption of daunorubicin and etoposide, respectively. Experimental findings also confirmed molecular dynamics simulation results. Communicated by Ramaswamy H. Sarma.

Impaired Autobiographical Memory Flexibility in Iranian Trauma Survivors With Posttraumatic Stress Disorder.

Reduced ability to retrieve specific autobiographical memories is a well-defined feature of posttraumatic stress disorder (PTSD), and science-driven interventions have emerged to improve memory specificity and thereby symptoms. However, research in depressed samples indicates that the ability to flexibly move between retrieval of specific and general memory types (i.e., memory flexibility) may more accurately conceptualize autobiographical memory deficits in emotional disturbance. In this study, we evaluated memory specificity and memory flexibility in Iranian trauma survivors (N = 63) with and without PTSD relative to community control participants. Trauma-exposed participants had experienced a serious road-traffic accident. Results indicated that individuals with PTSD experienced reduced memory specificity and memory flexibility relative to trauma-exposed participants and community control participants. A small sample size limits the strength of conclusions, although good statistical power was obtained. Findings suggest that reduced memory flexibility may be a transdiagnostic marker of emotional disturbance and support further development of memory flexibility interventions for PTSD.